1. Field of the Invention.
This invention relates to medical devices in general and, more particularly, to hemostasis introducer devices and methods of manufacture therefor. The hemostasis introducer provided by this invention is used as an ingress/egress point to the vascular system of a patient, for example, during angioplasty. The introducer seals the puncture to prevent leakage of blood therefrom. A radiopaque marked tip of the introducer allows the user to properly position the device within the vasculature and for calibration of related medical devices.
2. Background Information.
Various surgical procedures are performed by medical specialists such as cardiologists and radiologists, using percutaneous entry into a blood vessel or body cavity. Examples of such procedures include techniques to recanalize atherosclerotic blood vessels, such as balloon angioplasty, atherectomy or stent placement. Recently, both the types and number of procedures performed using the above mentioned percutaneous access to blood vessels have increased greatly.
These procedures generally involve the percutaneous puncture with a thin-walled needle into a blood vessel. Following this, a guidewire is placed through the needle into the blood vessel and the needle is withdrawn. An intravascular introducer or sheath of variable size, in combination with a tissue dilator, is then advanced over the guidewire, percutaneously, into the lumen of the blood vessel. The introducer is then used as an ingress/egress means during the procedure. Catheters, balloon devices, guidewires, stents filters and other medical devices may be inserted, manipulated and removed in and from the introducer. The placement of such catheters and other devices is typically monitored by a fluoroscope.
Introducers generally comprise a sheath, the proximal end of which is capped and sealed with an elastomeric gasket or valve. The gasket typically has an aperture through its center which seals against blood pressure in the body while allowing insertion or introduction of a catheter or stent through the gasket aperture, down the sheath, and into the blood vessel.
The marking of intravascular devices with radiopaque materials to indicate their position within the body is known. However, the particular materials and methods used for marking have various limitations. Specifically, the materials and methods are not optimally suited to the materials of which the introducers and sheaths are constructed. Additionally, prior art marker designs are at risk of failure due to differential expansion and contraction of the substrate and marker structures and compositions which commonly occurs during use. Finally, insofar as is known, no hemostasis introducer includes a marker that is useable to calibrate fluoroscopic equipment and the like, which are used to view introducer placement.
Despite the need in the art for an introducer and method of manufacture therefor which overcome the limitations and problems of the prior art, none insofar as is known has been proposed or developed. The present invention is specifically directed to overcoming all of the problems previously enumerated regarding the structure and performance of intravascular introducers and sheaths.